2-Story stone clad wall - how to distribute vertical load over a protrusion?

In designing the front of my house I want to achieve a certain look - a two story stone clad wall - but I want to design so that it is actually buildable without causing all sorts of headaches. So, with the stone transferring load down onto a brick ledge in the foundation wall, I'm concerned about two different features I want to incorporate into the wall. The first is large windows. If I want the stone cladding to continue above the first floor windows I'm going to have to deal with the weight of the stone above the window. I'm assuming that load paths can be addressed by directing the load with an arch over the window. How is this issue actually addressed? The second issue is I would like to have an entry/vestibule bumpout, of 2' - 5' depending on design considerations. I'd rather not bump out the full basement foundation, with brick ledge, to accommodate this feature, so is there a way to also have this small room be clad with stone without having to go with the foundation bumpout and, as with the window example, how would the load of the stone that continues above this entry bumpout be transferred to the brick ledge? I'm not looking for exact engineering calculations, just some insight that I can use in the design process without creating an expensive problem during the engineering vetting, in other words, if you guys could share some wisdom with me on what is practicable, then I can avoid designing a problematic feature.

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2-Story stone clad wall - how to distribute vertical load over a protrusion?

In designing the front of my house I want to achieve a certain look - a two story stone clad wall - but I want to design so that it is actually buildable without causing all sorts of headaches. So, with the stone transferring load down onto a brick ledge in the full basement foundation wall, I'm concerned about two different features I want to incorporate into the wall.

The first is large windows. If I want the stone cladding to continue above the first floor windows I'm going to have to deal with the weight of the stone above the window. I'm assuming that load paths can be addressed by directing the load with an arch over the window. How is this issue actually addressed?

The second issue is I would like to have an entry/vestibule bumpout, of 2' - 5' depending on design considerations. I'd rather not bump out the full basement foundation, with brick ledge, to accommodate this feature, so is there a way to also have this small room be clad with stone without having to go with the foundation bumpout and, as with the window example, how would the load of the stone that continues above this entry bumpout be transferred to the brick ledge?

I'm not looking for exact engineering calculations, just some insight that I can use in the design process without creating an expensive problem during the engineering vetting, in other words, if you guys could share some wisdom with me on what is practicable, then I can avoid designing a problematic feature.

2-Story stone clad wall - how to distribute vertical load over a protrusion?

I would consider hiring a design engineer to help you with this. It sounds like you want to hang a lot of weight in thin air. Stone work is not very receptive to any movement so a solid foundation and support system will be needed

2-Story stone clad wall - how to distribute vertical load over a protrusion?

I don't know if this will be any help, but in UK an increasing number of houses are being built with timber inner skins but clad in brick. Several manufacturers have devloped lintels for use over window and door openings - see attachment. These would only do for 4" thick units, though. Maybe your stone would be thicker? Presumably there will be something similar where you are.

Failing that, could you get an SE to design you some re-constructed stone lintels?

2-Story stone clad wall - how to distribute vertical load over a protrusion?

I'll be using real stone, 3" -4" thick, resting on a brick ledge in the full height basement foundation wall, so no peel and stick and no cultured stone. I wouldn't expect that this is an uncommon problem. Surely most houses with 2 story stone work have windows and doors in the walls. How do the stone masons work to distribute the load of the stone above? I know that the simplest solution here is to simply bypass the problem and this can be done by not putting stone work above windows and doors, simply taking the stone up to 4' or so and then cladding the wall with some other material. The prefab lintel looks like a solution. I'll have to look into that. I'm wondering though if stone masons actually fabricate their own stone lintels and arches with keystones out on the job site without needing SE designing the systems. I don't know but I want to learn. Hopefully someone who does this for a living will see this thread and add their wisdom.

2-Story stone clad wall - how to distribute vertical load over a protrusion?

Typically, it depends on the desired look and the shape of the window. Arches can work just fine, but they need to have enough radius, meaning that can't be too "flat".

If you don't necessarily want an arch, you can use a simple steel angle iron lintel, but be aware that you'll see one of the steel legs exposed from the underside.

One other option is to lay a masonry lintel (Indiana Bedford stone in this case) and set the steel lintel directly over the top of the stone. In this case, the stone is strong enough to carry the span of it's own weight, but the additional load of the stone above is pushing the limits w/o the steel angle.

2-Story stone clad wall - how to distribute vertical load over a protrusion?

Thank you for the detailed explanation and the photos. Are these solutions developed on site by the stone masons or are the masons fulfilling the requirements as spelled out by an engineer. Or to ask a variation on the above, do masons use the equivalent of load tables developed for beams in that an arch of x radius is good for an opening of Y width or a horizontal lintel of Y length can carry x lbs of load per foot, where load is determined by material and height of stonework above the lintel?

2-Story stone clad wall - how to distribute vertical load over a protrusion?

You could bridge the openings with hot-rolled steel angle, but it is not generally good practice. Over time, the steel rusts, and while it certainly won't collapse,the rust expands, causing slight lifting and cracking of the joints each side of the opening.

If you want to do it properly, construct arches in the traditional way using temporary timber formwork. The attachments show the idea (they show 4" thick brick but the principle holds for stone). The formwork is usually made out of 2x4, often with plywood bracing and stiffening. Once the arch is set, it is carefully removed.

Despite what you may have been told, in normal domestic loadings, there is no direct correlation between the rise of an arch, the span, and the depth of the arch units. But, the most important point is that there must be sufficient width and weight of masonry each side of the arch (known as the 'abutment') to provide lateral support. Arches exert sideways thrust and this must always be adequately resisted by weight.

2-Story stone clad wall - how to distribute vertical load over a protrusion?

Quote:

Originally Posted by AlexHouse

Thank you for the detailed explanation and the photos. Are these solutions developed on site by the stone masons or are the masons fulfilling the requirements as spelled out by an engineer. Or to ask a variation on the above, do masons use the equivalent of load tables developed for beams in that an arch of x radius is good for an opening of Y width or a horizontal lintel of Y length can carry x lbs of load per foot, where load is determined by material and height of stonework above the lintel?

I have some basic engineering available from previous projects for angle lintels, but for more complicated openings, I'll have the builder/GC aquire the info from the architect or engineer. As for arches, it's more of an experience thing.

Here's more info than you'll ever want on steel angle lintels, and by searching the site a bit more, you'll find alot of infon on arches as well. Note how load of masonry actually loads on the lintel or arch.